Background: At a landmark meeting in November 1999, the directors and staff of the major components of NIH conducting Parkinson's disease (PD) research, working together with patient advocates, initiated a planning process to ensure that extraordinary opportunities to move toward a cure for PD are adequately supported and that critical obstacles to progress are addressed. On January 4-6, 2000, a Workshop including intramural, extramural and industry scientists, representatives from several Parkinson's advocacy groups, and ethicists discussed an agenda for PD research and identified major areas to be investigated. These were summarized in an NIH Report to Congress outlining a research agenda for Parkinson's focused research for the next five years (Conference Report No. 106-479). This conference grant application requests funds from the major NIH Institutes conducting Parkinson's disease (PD) research to help support the 19th International Neurotoxicology Conference (NTX XIX) to be held August 25-28, 2001 in Colorado Springs, CO. The NTX XIX Conference will focus on the theme of "Parkinson's Disease, Environment and Genes." Significance: "A new optimism that Parkinson's disease can be defeated is energizing the research community and patient advocates. Halting the progression of PD, restoring lost function, and even preventing the disease are all realistic goals. This hope is fueled by the accelerating pace of discovery in neuroscience research generally, by advances in understanding what causes PD, and by a wide range of new treatments on the horizon including stem cell transplants, precision surgical repair, chronic brain stimulation, and natural growth factors to name a few. Optimism is tempered by the recognition that we cannot yet cure any major neurodegenerative disorder, and defeating PD requires crossing a major frontier of medicine" (NIH Report to Congress, 2000). Specific Aims: There is recent and increasing evidence of interaction between environmental exposures and genetic susceptibility in the etiology of PD. NTX XIX will address the major topic areas identified in the NIH Report while focusing on the role of environment and genes from an interdisciplinary perspective, i.e., toxicology, epidemiology, genetics, exposure assessment, clinical medicine, drug development and animal models. Our traditionally successful conference format will be followed; this includes: keynote speakers, tutorials to provide a framework on which to build, invited plenaries by recognized experts, informal in-depth discussion groups, platform sessions for the best papers selected from abstracts, poster session, post-doctoral and graduate student awards for best presentations to encourage young researchers in the field World class experts on these topics have been identified, invited and the most already have agreed to participate. Representatives from academia, industry, government, special interest groups, foundations and patient advocates are included. New and state-of-the-science research will be presented and discussed and research recommendations will be itemized for each topic. As has been done for the 18 previous conferences, papers from NTX XIX will be peer-reviewed and rapidly published.